1. Field of the Invention
The present invention relates generally to ink cartridges. In particular, the present invention is directed towards ink cartridges which may be used in combination with ink jet printers.
2. Description of Related Art
A known recording apparatus may be configured to detect when an amount of ink within an ink cartridge is less than a sufficient amount of ink. For example, a known ink cartridge may include a float which floats on the ink within the ink cartridge, and a known recording apparatus may include an optical sensor positioned on the side of the ink cartridge. When there is a sufficient amount of ink within the ink cartridge, the float is positioned above the optical sensor, and the light emitted by the optical sensor is not blocked by the float. Nevertheless, as the ink within the ink cartridge is consumed by the recording apparatus, the surface of the ink within the ink cartridge moves downward, which causes the float to also move downward. When the surface of the ink moves down to a predetermined level, the light from the optical sensor is blocked by the float, and the printer determines that there is an insufficient amount of ink within the ink cartridge.
Another known ink cartridge may include an ink container which is configured to store ink and a case which may substantially cover the entire body of the ink container. The ink container may include a frame and a film which may be connected to the frame to cover an opening of the frame and to form an ink chamber. The pressure inside the ink cartridge is less than the atmospheric pressure before the ink cartridge is mounted to the recording apparatus. Consequently, the film may deform inward, which reduces a storage capacity of the ink chamber.